The Camera Shutter and Shutter Speeds

The function of the camera shutter is to open and then close after a specific length of time so that light coming through the camera lens may reach the image sensor. The characteristics (intensity and colors) of the light is read by the image sensor and those characteristics are reproduced as an image or picture. The length of time that the shutter remains open during an exposure (when the shutter release is pressed) is called the shutter speed.

The Camera Shutter and Exposure: The camera shutter, lens aperture, and iso settings work together to produce images that are "correctly" exposed or exposed to the photographers preference. Those three functions are commonly referred to as the "Exposure Triangle". Check the Camera Exposure Basics page for more on how they work together

The shutter speed settings can be adjusted so that the camera will produce lighter or darker images by increasing or decreasing the length of time that the shutter is open. The camera shutter speed also affects the look of motion in a scene. (that will be discussed later in this article)

Image #1, Shutter Speed 1/250 Second, Aperture F11, ISO 800

Image #2, Shutter Speed 1/125 Second, Aperture F11, ISO 800

Image #3, Shutter Speed 1/60 Second, Aperture F11, ISO 800

The three pictures above are examples of how the shutter speed can affect the exposure (lightness or darkness) of an image. The camera settings for all three pictures was the same except for the shutter speed. ​Take note of the shutter speed listed under each image. You will understand why each picture is darker or lighter than the other as you continue to read.

Shutter Speeds: As was previously mentioned, the length of time the camera shutter stays open during an exposure is called the shutter speed. The shutter speed is usually expressed in fractions of a second as shown below although the time can be longer during some exposures.

The chart above lists some of the standard shutter speeds as full steps. Changing the shutter speed from any one of those settings to the adjacent one will either double or cut in half the amount of time camera shutter remains open. So it follows that changing the shutter speed from any one of the above settings to an adjacent one will double or cut in half the length of time the light is exposed to the image sensor.

Any increase or decrease in the shutter speed will cause the image to be lighter or darker. That is, as long as the lens aperture and ISO settings remain the same. Images will be lighter as the shutter stays open longer to expose the light to the image sensor.

Take another look at the 3 pictures above and take note of the following: a 1/60 sec shutter speed will keep the camera shutter open about twice as long as a 1/125 sec shutter speed. On the other hand, the 1/250 sec shutter speed leaves the camera shutter open half the length of time as the 1/125 shutter speed. So now you can understand why each Image is darker or lighter than the other.​Please note that the "B" (Bulb) setting is not a preset amount of time that the camera shutter will remain open. The "B" setting found on cameras like the Nikon D5500, is a manual setting that allows the shutter to be open for an indefinite amount of time. The length of time that the camera shutter remains open is determined by the photographer.

Your camera probably has shutter speeds that are programmed in smaller steps than those that are listed above. So, for reference, the shutter speed chart below lists some of the most common shutter speeds in 1/3 steps.​ The shutter speeds in red are full steps apart.

​Shutter Speeds and Motion: In addition to allowing light to reach the image sensor, the camera shutter will affect how any motion in a scene will appear in your image. Motion in a photo image can be "frozen" or appear as blurred. Take a look at the pictures of the 2 cars below.​​

Image#4, Shutter Speed 1/60 second, Shows Motion Blur

Image #5, Shutter Speed 1/400 second, Freezes Motion

​The car in picture #1 was moving around 30 mph. Notice that just about everything in the image is in focus except the car. This is an example of what is known as motion blur.

The car is not in focus because the shutter speed of 1/60 sec was not fast enough to "freeze" it's motion. In some cases this type of blur might be desirable because it actually conveys a sense of motion. However, if you want your moving subject to be in focus, you will need to use a faster shutter speed that will freeze the motion.

The car in picture #2 was also moving about 30 mph, yet the car and everything else in the scene is in focus. That is because in this case a faster shutter speed (1/400 sec) was used. The shutter speed was fast enough to freeze the motion without the blur. The shutter speed of 1/400 worked well to freeze the motion in this case, but when taking pictures of faster moving subjects, a shutter speed of 1/500 or higher is usually a better choice.

Image #6, Shutter Speed 1/800 second

Image #7, Shutter Speed 1/15 second

Another example of how the shutter speed affects the look of motion in an image is shown in the two pictures of the water fountain above. Image #6 was taken using a pretty fast shutter speed of 1/800 second. As you can see, most of the water droplets are "frozen" in mid air.

​On the other hand, image #7 was taken with a very slow shutter speed of 1/15 second and the water shows as a silky blur. Both of the shutter speeds used were effective in creating nice images. The choice as to whether to use a very fast or very slow shutter speed depends on the effect the photographer wants.

Slower Shutter Speeds: It is important to note that when you use very slow shutter speeds, (1/30 second or slower) it is a good idea to use a tripod. Camera shake and the blur that comes with it increases greatly at slower shutter speeds. When the camera is hand held and a very slow shutter speed like 1/15 second is used, there is a strong possibility that the whole image will be out of focus due to camera shake. Check the Night Photography tutorial for more on this subject.

​Choosing a Shutter Speed: If there is motion in a scene that you are photographing, the best shutter speed to use will vary depending on the speed of that motion, or the desired effect of the motion. (subject frozen or blurred) Listed below are some common picture taking situations and shutter speeds that can be used as starting points.*

​*Depending on the available light, adjustments to the lens aperture and ISO settings may be required to use the desired shutter speed. Check the Camera Exposure Basics tutorial on how adjustments may be made.

There may be times when a slow shutter speed is more desirable or necessary, especially in low light situations. A couple of situations that would require a slower shutter speed would be a fireworks display or night pictures at an amusement park. (see pictures #8 and #9) In these cases a very slow shutter speed, coupled with motion make for fun and interesting pictures.

All of the cameras that were just mentioned also allow you to manually set the lens aperture, ISO setting, and many other features so that you have more creative control over your pictures.

If you are using a very basic compact camera, you probably wont be able to manually adjust your shutter speed. However, basic compact cameras have automatic scene modes that can be set to match the type of scene you are photographing.

The camera will automatically set the best shutter speed for that type of scene. Please see the tutorial on Automatic Shooting Modes for a little more on that subject.

Hopefully, you now have a good understanding of the camera shutter function. Practice using the various shutter speeds to fit the situation, then add your own creativity and your pictures should be fine!